Emergency Alerts & Preparedness
Radiation Card Explained
The Radiation card counts elevated public radiation readings on the map, primarily from EPA RadNet when valid current data is available.
Quick read
- Useful for
- Radiation monitoring is highly context-dependent. A dashboard can show public sensor context, but official agencies and emergency alerts are the authority for protective actions.
- Watch
- elevated readings, station coverage, dose rate, unit, source, station, stream type, status, threshold, and generated/fallback warnings.
- Confirm with
- EPA RadNet and Ready.gov
- Remember
- Gamma gross count rate is not directly comparable to dose-rate thresholds, and generated fallback data must not be treated as live measurement.
How to read this card
- Value: number of displayed readings at or above the current dashboard radiation threshold.
- Context: Elevated readings or Feed unavailable depending on selected feed status.
- Radiation threshold: settings value in µSv/h used for card filtering/counting.
- Coverage: station/read count label such as stations read out of approximate EPA RadNet monitors.
Hover and popup metrics explained
- Dose rate/value: displayed in µSv/h when stream type supports dose/exposure comparison.
- Normal/elevated: elevated means at or above the selected threshold; normal means below threshold in displayed current data.
- Station: EPA RadNet monitor or source-provided location label.
- Stream type: dose-equivalent/exposure-rate can be compared to the dashboard threshold; gamma-gross-count is not directly comparable.
- Source: EPA RadNet, Safecast, generated-dev-fallback, or unknown metadata depending on the feed.
- Status: normal/current, elevated, stale, not current, or generated background proxy based on reading metadata.
- Station coverage: how much monitor coverage the current feed represents.
What can make this status change?
- A current RadNet reading crosses the selected threshold.
- Station coverage changes after a refresh.
- A stale/generated fallback is rejected or replaced by real current data.
- The user changes the radiation threshold setting.
Limitations
Radiation sensor units and stream types matter. Crowdsourced or mobile survey readings can be useful context but are not the same as a fixed official station. Generated fallback rows are diagnostics and should not drive safety conclusions.
Sources and update behavior
HazardNow filters production dashboard radiation toward valid current public data and ignores known poisoned legacy/generated diagnostics for production selection. Source refreshes are cached.
Visual reference
Radiation card signal map
Read the signal as one layer in a larger source stack, not as a standalone instruction.
Official/public sources
Use these links to verify current source text, update timing, and agency caveats.
FAQ
Does zero elevated readings prove safety?
No. It means no displayed current readings exceeded the dashboard threshold under available coverage. Coverage and freshness limitations still matter.